Magnetism and Motor Effect Flashcards
How can a magnet be used to sort aluminium cans from steel cans.
The magnet will attract the steel cans only, because steel is a magnetic material and aluminium is not magnetic.
What is an induced magnet?
When a magnetic material is placed in a magnetic field and becomes a magnet itself.
What is a uniform magnetic field?
Has the same strength and direction everywhere.
What is meant by solenoid?
A coil of wire, with current flowing through it.
Where is the magnetic field strongest in a solenoid?
Inside the coil, because the fields reinforce each other.
What is the advantage of an electromagnet vs a permanent magnet?
The electromagnet can be turned on and off.
In the right hand rule, what do the thumb and fingers represent?
Fingers = direction of the magnetic field Thumb = the direction of current
Describe two ways in which the magnetic field around a wire can be changed.
Increase current and change the direction of current
What is the motor effect?
A force experienced by a wire carrying a current in a magnetic field.
In Flemings left hand rule, what do the thumb, index finger and middle finger represent?
Thumb = direction of force Index = direction of magnetic field Middle = direction of current
